Question

我需要一个实现拖放和缩放的解决方案，在不使用矩阵的情况下在屏幕onTouch事件周围路由ImageView。我搜索了很多，但所有的答案用矩阵完成它因为我在屏幕矩阵中有多个对象不适合我，我想在ImageView中拖动和缩放ImageView对象而不是矩阵，经过一些尝试我实现了一个拖动视图的类很好但是放大它会打扰，谢谢，如果有人可以帮助我，抱歉语言能力差，如果我拼错了。

package com.example.painting1;

import android.graphics.PointF;
import android.util.FloatMath;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.ImageView;

public class Drag implements OnTouchListener {

    ImageView img;

    // We can be in one of these 3 states
    private static final int NONE = 0;
    private static final int DRAG = 1;
    private static final int ZOOM = 2;

    private int mode = NONE;

    private PointF mid = new PointF();

    PointF DownPT = new PointF(); // Record Mouse Position When Pressed Down
    PointF StartPT = new PointF(); // Record Start Position of 'img'

    float oldDist = 1f;

    public Drag( ImageView img ) {
        // TODO Auto-generated constructor stub
        this.img = img;
        img.setOnTouchListener(this);
    }

        private float spacing(MotionEvent event) {
            float x = event.getX(0) - event.getX(1);
            float y = event.getY(0) - event.getY(1);
            return FloatMath.sqrt(x * x + y * y);
        }

        /**
         * Calculate the mid point of the first two fingers
         */
        private void midPoint(PointF point, MotionEvent event) {
            float x = event.getX(0) + event.getX(1);
            float y = event.getY(0) + event.getY(1);
            point.set(x / 2, y / 2);
        }

        @Override
            public boolean onTouch(View v, MotionEvent event)
            {
                int evid = event.getAction();
                int moid = MotionEvent.ACTION_MASK;

                switch (evid & moid)
                {
                    case MotionEvent.ACTION_MOVE :

                       if (mode == DRAG) {                      
                                PointF mv = new PointF( event.getX() - DownPT.x, event.getY() - DownPT.y);
                                img.setX((int)(StartPT.x+mv.x));
                                img.setY((int)(StartPT.y+mv.y));
                                StartPT = new PointF( img.getX(), img.getY() );
                        }

                         else if (mode == ZOOM) {
                                    float newDist = spacing(event);
                                    if (newDist > 10f) {
                                        //matrix.set(savedMatrix);
                                        float scale = (newDist / oldDist);
                                        //matrix.postScale(scale, scale, mid.x, mid.y);

                                        img.layout((int)scale, (int)scale, (int)mid.x, (int)mid.y);

                                        img.setScaleX(scale);
                                        img.setScaleY(scale);
                                    }
                         }

                        break;

                    case MotionEvent.ACTION_DOWN :

                        mode = DRAG;

                        DownPT.x = event.getX();
                        DownPT.y = event.getY();
                        StartPT = new PointF( img.getX(), img.getY() );
                        break;
                    case MotionEvent.ACTION_UP :
                        // Nothing have to do
                    case MotionEvent.ACTION_POINTER_UP :
                            mode = NONE;
                        break;

                    case MotionEvent.ACTION_POINTER_DOWN :

                        oldDist = spacing(event);
                        if (oldDist > 10f) {
                            //savedMatrix.set(matrix);
                            midPoint(mid, event);
                            mode = ZOOM;
                        }
                        break;
                    default :
                        break;
                }
                return true;
        }
}

Answer 1

试试此代码

I have a solution for you,I wish it will work for you,

try to use TouchImageView instead of ImageView in Layout.because touchimageview have property that zooming in or out itself

https://github.com/MikeOrtiz/TouchImageView

通过此链接，您将学习如何使用touchimageview ...

<com.luminous.pick.TouchImageView
                android:id="@+id/img2"
                android:layout_width="match_parent"
                android:layout_height="match_parent" />

Then After implement onDragListener of TouchImageView so you can get DRAG And Drop of Imageview easily...

@Override
public boolean onDrag(View v, DragEvent event) {

    switch (event.getAction()) {

        case DragEvent.ACTION_DROP:

            TouchImageView target = (TouchImageView) v;
            TouchImageView dragged = (TouchImageView) event.getLocalState();

            Drawable target_draw = target.getDrawable();
            Drawable dragged_draw = dragged.getDrawable();

            dragged.setImageDrawable(target_draw);
            target.setImageDrawable(dragged_draw);

   }
    return true;
}

Answer 2

**这是Zoom，Drag，Touchable ImageView的完整源代码。

在对图像执行拖动和缩放时，它工作流畅。**

package com.admin.imagemovementzoom;

import android.annotation.SuppressLint;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.graphics.drawable.BitmapDrawable;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.FloatMath;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.animation.LinearInterpolator;
import android.widget.ImageView;
import android.widget.RelativeLayout;

import com.squareup.picasso.Picasso;


public class FullmageActivity extends AppCompatActivity implements View.OnTouchListener {

    private ImageView img_fullimage;
    private String picturePath;


    private static final String TAG = "Touch";
    // These matrices will be used to move and zoom image
    Matrix matrix = new Matrix();
    Matrix savedMatrix = new Matrix();

    // We can be in one of these 3 states
    static final int NONE = 0;
    static final int DRAG = 1;
    static final int ZOOM = 2;
    int mode = NONE;

    // Remember some things for zooming
    PointF start = new PointF();
    PointF mid = new PointF();
    float oldDist = 1f;

    @SuppressLint("ClickableViewAccessibility")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fullmage);

        picturePath = getIntent().getStringExtra("image");

        FindId();

        Log.d("adaa", "file://" + picturePath);

        Picasso.get().load("file://" + picturePath).into(img_fullimage);

        img_fullimage.setOnTouchListener(this);
        img_fullimage.setScaleType(ImageView.ScaleType.MATRIX);

    }


    private void FindId() {
        img_fullimage = findViewById(R.id.img_full);
    }


    /**
     * Called when a touch event is dispatched to a view. This allows listeners to
     * get a chance to respond before the target view.
     *
     * @param v     The view the touch event has been dispatched to.
     * @param event The MotionEvent object containing full information about
     *              the event.
     * @return True if the listener has consumed the event, false otherwise.
     */
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        ImageView view = (ImageView) v;

        // Dump touch event to log
        dumpEvent(event);

        // Handle touch events here...
        switch (event.getAction() & MotionEvent.ACTION_MASK) {
            case MotionEvent.ACTION_DOWN:
                savedMatrix.set(matrix);
                start.set(event.getX(), event.getY());
                Log.d(TAG, "mode=DRAG");
                mode = DRAG;
                break;
            case MotionEvent.ACTION_POINTER_DOWN:
                oldDist = spacing(event);
                Log.d(TAG, "oldDist=" + oldDist);
                if (oldDist > 10f) {
                    savedMatrix.set(matrix);
                    midPoint(mid, event);
                    mode = ZOOM;
                    Log.d(TAG, "mode=ZOOM");
                }
                break;
            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_POINTER_UP:
                mode = NONE;
                Log.d(TAG, "mode=NONE");
                break;
            case MotionEvent.ACTION_MOVE:
                if (mode == DRAG) {
                    // ...
                    matrix.set(savedMatrix);
                    matrix.postTranslate(event.getX() - start.x,
                            event.getY() - start.y);
                } else if (mode == ZOOM) {
                    float newDist = spacing(event);
                    Log.d(TAG, "newDist=" + newDist);
                    if (newDist > 10f) {
                        matrix.set(savedMatrix);
                        float scale = newDist / oldDist;
                        matrix.postScale(scale, scale, mid.x, mid.y);
                    }
                }
                break;
        }

        view.setImageMatrix(matrix);
        return true; // indicate event was handled
    }

    /**
     * Show an event in the LogCat view, for debugging
     */
    private void dumpEvent(MotionEvent event) {
        String names[] = {"DOWN", "UP", "MOVE", "CANCEL", "OUTSIDE",
                "POINTER_DOWN", "POINTER_UP", "7?", "8?", "9?"};
        StringBuilder sb = new StringBuilder();
        int action = event.getAction();
        int actionCode = action & MotionEvent.ACTION_MASK;
        sb.append("event ACTION_").append(names[actionCode]);
        if (actionCode == MotionEvent.ACTION_POINTER_DOWN
                || actionCode == MotionEvent.ACTION_POINTER_UP) {
            sb.append("(pid ").append(
                    action >> MotionEvent.ACTION_POINTER_ID_SHIFT);
            sb.append(")");
        }
        sb.append("[");
        for (int i = 0; i < event.getPointerCount(); i++) {
            sb.append("#").append(i);
            sb.append("(pid ").append(event.getPointerId(i));
            sb.append(")=").append((int) event.getX(i));
            sb.append(",").append((int) event.getY(i));
            if (i + 1 < event.getPointerCount())
                sb.append(";");
        }
        sb.append("]");
        Log.d(TAG, sb.toString());
    }

    /**
     * Determine the space between the first two fingers
     */
    private float spacing(MotionEvent event) {
        float x = event.getX(0) - event.getX(1);
        float y = event.getY(0) - event.getY(1);
        return (float) Math.sqrt(x * x + y * y);
    }

    /**
     * Calculate the mid point of the first two fingers
     */
    private void midPoint(PointF point, MotionEvent event) {
        float x = event.getX(0) + event.getX(1);
        float y = event.getY(0) + event.getY(1);
        point.set(x / 2, y / 2);
    }
}

拖动，缩放imageview没有矩阵android

2 个答案: